Polydopamine-modified HKUST-1 as nanofiller of PPS@PA membrane with well improved desalination performance

Abstract

In order to improve the permeability and desalination performance of the thin-film nanocomposite (TFN) membranes supported by polyphenylene sulfide ( PPS ), the polydopamine (PDA) modified HKUST-1 (mHKUST-1) nanocomposite materials were added into polyamide ( PA ) functional layer. The mHKUST-1 nanoparticles with good dispersity and chemical compatibility were successfully embedded in PA layer to develop a new negative charged nanofiltration membrane. The optimized PPS/12-mHKUST-1@PA membrane showed an excellent permeability of up to 27.35 L∙m −2 h −1 ∙bar −1 , twice as much as the PPS@PA membranes. Meanwhile, the considerable rejection performance of 91.67% to MgSO 4 and 90.06% to Na 2 SO 4 at 4 bar was mainly up to the repulsive effect of negative charge on membrane surface. Moreover, the PPS/mHKUST-1@PA membranes also has stable filtration performance under long time operation. The results suggested that the membrane modification method in this work have great potential for applications in desalination. • The perfect separation layer by mHKUST-1 nanoparticles combined well with PA layer. • Improving the permeability and desalination performances of TFN membranes significantly. • Negatively charged of TFN membranes surface for the separation of sulfate and hydrochloride.